Zero-velocity/course correction application online calibrating method for optical fiber strapdown inertial measuring unit

Abstract

The invention discloses a zero-velocity / course correction application online calibrating method for optical fiber strapdown inertial measuring unit, and belongs to the field of inertial technology. A carrier erection two-position aligning process is utilized sufficiently, main error sources including drift errors, scale errors, mounting errors and the like of the optical fiber inertial measuring unit are calibrated by a filtering method on the basis of zero-velocity correction and heading correction, and the actual use precision of the optical fiber inertial measuring unit is improved. Output data of an optical fiber gyro and output data of a quartz accelerometer are acquired by determining parameters of the initial position of a carrier; the gesture of the carrier is determined by means of coarse alignment; and online calibration is realized by precise alignment for a horizontal position and a vertical position. The method is used for calibrating main error items of the optical fiber inertial measuring unit, so that the parameter identification precision of a system and an actual navigation performance of the optical fiber strapdown inertial measuring unit are improved.

Description

Technical field [0001] The invention belongs to the technical field of inertia, and specifically relates to an online calibration method of optical fiber strapdown inertial group using zero-speed / heading correction. Background technique [0002] Fiber optic gyroscope is an angular rate sensor based on the SAGNAC effect. Compared with traditional mechanical gyroscopes, fiber optic gyroscopes have the advantages of simple structure, stable performance, wide dynamic range, instantaneous response, large overload, relatively low price, and long life. It has attracted the general attention of manufacturers and users in various countries, and its development is quite similar. rapid. [0003] The fiber optic strapdown inertial group is generally composed of three fiber optic gyroscopes, three quartz flexible accelerometers and system related circuits. The fiber strapdown inertial unit generally needs to complete the initial alignment process before entering the navigation solution state....

AI Technical Summary

Problems solved by technology

[0008] The disadvantage of the above two alignment methods is that only the gyro drift error can be estimated, and the installation error and scale error of the optical fiber inertial group are not considered. The improvement of the inertial group accuracy is limited, thus limiting the actual navigation performance of the inertial group.

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